On the server platform..... On the desktop platform.... On the mobile platform..... Pick one. Have we not learned from the past that there really is not a one

On the server platform..... On the desktop platform.... On the mobile platform..... Pick one. Have we not learned from the past that there really is not a one size fits all operating system for all use cases. I am probably alone in thinking this, but bad decisions can be made when trying to get a server OS to run on a phone.